Methods and apparatus using energized fluids to clean chemical mechanical planarization polishing pads

ABSTRACT

Methods adapted to clean a chemical mechanical polishing (CMP) pad are disclosed. The methods include positioning an energized fluid delivery assembly over a CMP polishing pad; rotating the polishing pad on a platen; energizing a fluid within the energized fluid delivery assembly; applying the energized fluid to the polishing pad to dislodge slurry residue and debris; and removing the dislodged slurry residue and debris using a vacuum suction unit. Systems and apparatus for carrying out the methods are provided, as are numerous additional aspects.

FIELD

The present invention generally relates to electronic devicemanufacturing, and more particularly is directed to using fluids toclean chemical mechanical planarization (CMP) polishing pads.

BACKGROUND

The electronics industry currently spends in excess of one billion U.S.Dollars each year manufacturing silicon substrates that must exhibitvery flat and smooth surfaces. Known techniques to manufacture smoothand even-surfaced silicon substrates are plentiful. The most common ofthese involves the process known as chemical mechanical polishing (CMP)which includes the use of a polishing pad in combination with abrasiveslurry. Of central importance in CMP processes is the attainment of highperformance levels in aspects such as uniformity of polished substrate,smoothness of the IC circuitry, removal rate for productivity, longevityof consumables for CMP economics, etc. Chemical mechanical polishing(sometimes known in the art as chemical mechanical planarization), orCMP, is thus a well-known process used in the fabrication of electronicdevices. CMP combines mechanical polishing (using, for example, abrasiveslurries) with selective chemical reactions to increase the mechanicalremoval rate of material. The chemical reactions particularly providegreater material removal selectivity than mechanical polishing alone.

CMP is commonly used to flatten the surface of a substrate after etchand/or deposition steps, generally to such a degree that subsequentphotolithography steps have a sufficient focus margin. In general, CMPis performed by using a polishing pad in combination with a slurry ofwater, abrasives, and reactive chemicals for the desired chemicalreaction or reactions. The polishing pad is caused to be pressed againstthe substrate surface and relative motion between the substrate and thepad is imparted (that is, by moving one or both of the substrate and thepad).

The polishing pad is conventionally a porous pliable material.Polyurethane foam is particularly common for use as a polishing pad.Surface asperities of the polishing pad are critical to the polishingprocess because they provide the mechanical polishing action. However,as the pad is used for polishing, it tends to become smoother as theasperities are rubbed away and/or as slurry residues build up in thepores. As a result, the polishing process is degraded. It is thereforeconventionally known to condition the polishing pad to roughen thesurface and increase the open porosity of the foam.

Conventional conditioning methods however typically wear the polishingpad such that a given pad can only be conditioned a finite number oftimes before it must be discarded. Thus, what is needed are systems,methods, and apparatus that allow the useful life of CMP polishing padsto be extended, but still effectively remove slurry and debris from thepores and grooves of the pad without unnecessarily wearing the pad.

SUMMARY

Inventive embodiments of methods and apparatus are provided for cleaningslurry and debris from CMP polishing pads by applying energized fluidsto the polishing pads. Embodiments of the present invention useenergized fluid (e.g., liquids and gases) to clean off slurry residuesand pad debris between substrate polishing or during wafer polishing.During an energized fluid cleaning cycle, as the polishing pad issprayed or otherwise applied with energized liquids or gases that loosenand dislodge slurry residue and pad debris, a vacuum pump is used toremove the dislodged material. In some embodiments, a scraper, beater,and/or a rotating bristle brush may selectively, continuously, orintermittently contact the polishing pad to further help loosen anddislodge residue and debris. In some embodiments, instead of merelypressurizing a fluid, the energized fluid can be acoustically energized(e.g., via acoustic cavitation), pneumatically assisted (e.g., using aliquid mixed with a pressurized gas), and/or thermally state changed(e.g., liquid heated to gas). Other methods and combinations ofenergizing fluids can be used.

In some embodiments, a method for cleaning a chemical mechanicalpolishing (CMP) pad is provided. The method includes positioning anenergized fluid delivery assembly over a CMP polishing pad; rotating thepolishing pad on a platen; energizing a fluid within the energized fluiddelivery assembly; applying the energized fluid to the polishing pad todislodge slurry residue and debris; and removing the dislodged slurryresidue and debris using a vacuum suction unit.

In some other embodiments, a system for cleaning a chemical mechanicalpolishing (CMP) pad is embodiment. The system includes a processor; anda memory storing instructions executable by the processor, theinstructions operative to: position an energized fluid delivery assemblyover a CMP polishing pad; rotate the polishing pad on a platen; energizea fluid within the energized fluid delivery assembly; apply theenergized fluid to the polishing pad to dislodge slurry residue anddebris; and remove the dislodged slurry residue and debris using avacuum suction unit.

In yet other embodiments, an apparatus for cleaning a chemicalmechanical polishing (CMP) pad is provided. The apparatus includes anenergized fluid delivery assembly configured to energize a fluid andapply the energized fluid to a CMP polishing pad to dislodge slurryresidue and debris from the polishing pad; and a vacuum suction unitconfigured to remove the dislodged slurry residue and debris.

In still yet other embodiments, a system for cleaning a chemicalmechanical polishing (CMP) pad is provided. The system includes apolishing pad configured to be rotated on a platen; a polishing headconfigured to hold a substrate against the polishing pad; and anenergized fluid delivery assembly configured to apply an energized fluidto the polishing pad to dislodge slurry residue and debris from thepolishing pad.

Numerous other aspects are provided. Other features and aspects of thepresent invention will become more fully apparent from the followingdetailed description, the appended claims and the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a schematic side-view drawing depicting an example ofa CMP system according to embodiments.

FIGS. 2A to 2C illustrates top, side, and front views respectively of aCMP polishing pad and an example of an energized fluid cleaning assemblyaccording to a first embodiment.

FIGS. 3A and 3B illustrates top and side views respectively of a CMPpolishing pad and an example of an energized fluid cleaning assemblyaccording to a second embodiment.

FIGS. 4A to 4C illustrates top, side, and front views respectively of aCMP polishing pad and an example of an energized fluid cleaning assemblyaccording to a third embodiment.

FIG. 5 illustrates a flowchart depicting an example method of cleaning aCMP polishing pad using energized fluid according to some embodiments.

DETAILED DESCRIPTION

Embodiments of the present invention provide improved systems, methodsand apparatus configured to clean slurry and debris from CMP polishingpads by applying energized fluids to the polishing pads. During CMP,slurries and pad debris are accumulated and become trapped within padgrooves and pores, which can cause scratches on the substrate beingpolished. Current state-of-the-art technology uses a high-pressure(e.g., ˜40 PSI) de-ionized water (DIW) rinse and/or vacuum to pick upsuch residues from the pad. However, the high-pressure DIW rinse andvacuum have been shown not to be sufficient to dislodge slurry/debrisresidues from the pad grooves and pores. Therefore, conventional methodsof using high-pressure DIW rinse and vacuum are not sufficient for padcleaning.

One or more embodiments of the present invention use energized fluid(e.g., liquids and gases) to clean off slurry residues and pad debrisbetween wafer polishing or during wafer polishing. During an energizedfluid cleaning cycle, as the polishing pad is sprayed or otherwiseapplied with energized liquids or gases that loosen and dislodge slurryresidue and pad debris, a vacuum pump is used to remove the dislodgedmaterial. In some embodiments, a scraper, beater, and/or a rotatingbristle brush may selectively, continuously, or intermittently contactthe polishing pad to further help loosen and dislodge residue anddebris. In some embodiments, instead of merely pressurizing a fluid, theenergized fluid can be acoustically energized (e.g., via acousticcavitation), pneumatically assisted (e.g., using a liquid mixed with apressurized gas), and/or thermally state changed (e.g., liquid heated togas). Other methods and combinations of energizing fluids can be used.In some embodiments, the present invention can be used for pad cleaning,pad conditioning, and brush break-in.

Turning to FIG. 1, a side view of an example chemical-mechanicalplanarization (CMP) system 100 for polishing substrates is shown. Thesystem 100 includes a polishing head assembly 102 supported by anpolishing head arm 104 operative to position the polishing head assembly102 over a polishing pad 106 supported by and rotated on a platen 108.The platen 108 is driven to rotate by a motor 110. In operation, thepolishing head assembly 102 is operative to securely hold a substrate,to rotate the substrate, and to press the substrate against the rotatingpolishing pad 106 during CMP processing. In other words, as thepolishing pad 106 is rotated on the platen 108, the head 102 rotates andpushes the substrate down against the polishing pad 106.

The system 100 also includes an energized fluid delivery assembly 112supported by fluid delivery arm 114. The fluid delivery arm alsosupports a vacuum suction unit 116 operative to remove residue anddebris dislodged by the application of the energized fluid to the CMPpolishing pad 106.

Each of the components can be coupled to, and operated by, a controller118 (e.g., a processor, programmable logic array, embedded controller,computer, etc.) operative to execute instructions (e.g., software,programs, commands, signals, etc.) to perform the methods of the presentinvention, and in particular, the methods described below with respectto the flowchart in FIG. 5.

As indicated above, the energized fluid can be acoustically energized.Ultrasonically or megasoincally energized fluid (e.g., fluid thatexperiences acoustic cavitation) can dislodge residues from large areaslike polishing pad grooves and also from smaller areas like polishingpad pores. This capability to dislodge particles from both larger andsmaller areas provides for a higher cleaning efficiency of the polishingpad as compared to conventional methods.

FIGS. 2A through 2C depict top, side and front views respectively of anenergized fluid delivery assembly 112 (FIG. 1) that includes anacoustically energized fluid delivery unit 212 that is adapted todelivery acoustically energized fluid 214 to the polishing pad 106 whilevacuum suction unit 116 removes dislodged residue and debris. In someembodiments, the acoustically energized fluid delivery unit 212 caninclude a piezoelectric transducer (PZT) operating in the frequencyrange from the lower ultrasonic range (approximately 20 KHz) to theupper megasonic range (approximately 2 MHz.) Other frequency ranges canbe used. The shape of a suitable acoustic energy source generator (e.g.,a PZT) can be rectangular with dimensions in the range of approximately5 mm×50 mm to approximately 15 mm×1500 mm. Other sized PZTs can be used.For example, with a polishing pad radius of 15 inches, a PZT with alength of 15 inches may be used. Likewise, the vacuum suction unit 116can be the same length.

In some embodiments, shorter length PZTs can be used in the acousticallyenergized fluid delivery unit 212 where the acoustically energized fluiddelivery unit 212 is adapted to be swept from the center of the pad 106to the edge of the pad 106. In such embodiments, the fluid delivery arm114 (FIG. 1), can be used to sweep the acoustically energized fluiddelivery unit 212 across the pad 106 radially. Alternatively, a separategantry can be used to sweep the acoustically energized fluid deliveryunit 212 back and forth radially over the pad 106.

In some embodiments, the acoustically energized fluid delivery unit 212can include a housing with an input channel to receive fluid, a PZT heldwithin the housing to apply energy to the received fluid, and a slot orplurality of nozzles along the bottom length of the housing aimed at thepolishing pad 106 to distribute the energized fluid 214 across thepolishing pad 106. In some embodiments, the housing or individualnozzles can be configured to rock back and forth as energized fluid 214is being dispensed to further enhance the loosening action of theenergized fluid 214 by continually altering the angle of impact of theenergized fluid 214 on the pad 106.

As indicated by the ‘H’ dimension labeled in FIGS. 2B and 2C, theacoustically energized fluid delivery unit 212 can be disposed fromapproximately 4 mm to approximately 10 mm above the polishing pad 106during application of the acoustically energized fluid 214. Likewise thevacuum suction unit can be similarly disposed from approximately 4 mm toapproximately 10 mm above the polishing pad 106 during application ofthe acoustically energized fluid 214.

In some embodiments, the fluid that is energized can be deionized water(DIW) and/or cleaning chemistry. The temperature of the fluid can befrom 20 C. to 90 C. Other temperatures can be used. The flow rate of theenergized fluid 214 can be in the range of approximately 100 ml/min toapproximately 10 L/min. Other flow rates can be used. In someembodiments, the cleaning chemistry can be, for example, dilutedpotassium hydroxide (KOH) when using, for example, SemiSperse® SS12slurry manufactured by Cabot Microelectronics Corporation of Aurora,Ill.

In some embodiments, a scraper, beater, and/or a rotating bristle brushmay selectively, continuously, or intermittently contact the polishingpad 106 to further help loosen and dislodge residue and debris. The useof a scraper, beater, and/or a rotating bristle brush may be selectivelyapplied by the controller 118. An optical sensor can be used to inspectthe pad 106 and provide information to the controller 118 as to thestatus of the pad 106. Based on the status of the pad 106, thecontroller 118 can determine if the pad should continue to be treatedwith energized fluid, if higher energy should be applied to the fluid(e.g., heat, pressure, acoustic energy, etc.), or of the pad shouldreceive contact from a scraper, beater, and/or a rotating bristle brush.

As indicated above, the energized fluid can alternatively be energizedusing pressurized gas. As with acoustically energized fluid, pressurizedgas assisted liquid spray jets can be used to effectively dislodgeresidue and debris from large areas like polishing pad grooves and alsofrom smaller areas like polishing pad pores. As noted, this capabilityprovides for high cleaning efficiency of the polishing pad as comparedto conventional pad cleaning methods. The pressurized gas assisted sprayremoves particles via fluid droplet momentum transfer. Because thismethod has a lower fluid flow rate, not only is DIW conserved, theamount of splash is drastically reduced and therefore, there issubstantially less slurry residue build up within the system 100.

FIGS. 3A and 3B depict top and side views respectively of an energizedfluid delivery assembly 112 (FIG. 1) that includes an pressurized gasenergized fluid delivery unit 312 that is adapted to deliverypressurized gas energized fluid 314 to the polishing pad 106 whilevacuum suction unit 116 removes dislodged residue and debris. In someembodiments, the pressurized gas energized fluid delivery unit 312 caninclude a pressurized gas supply such as filtered air or nitrogen (N₂).The mixing chamber within the pressurized gas energized fluid deliveryunit 312 can be rectangular with dimensions in the range ofapproximately 5 mm×50 mm to approximately 15 mm×1500 mm. Other sizedmixing chambers can be used. For example, with a polishing pad radius of15 inches, a mixing chamber with a length of 15 inches may be used.Likewise, the vacuum suction unit 116 can be the same length.

In some embodiments, shorter length mixing chambers can be used in thepressurized gas energized fluid delivery unit 312 where the deliveryunit 312 is adapted to be swept from the center of the pad 106 to theedge of the pad 106 as indicated by the double ended arrow in FIG. 3A.In such embodiments, the fluid delivery arm 114 (FIG. 1), can be used tosweep the pressurized gas energized fluid delivery unit 312 across thepad 106 radially. Alternatively, a separate gantry can be used to sweepthe pressurized gas energized fluid delivery unit 312 back and forthradially over the pad 106.

In some embodiments, the pressurized gas energized fluid delivery unit312 can include a housing with a liquid input channel to receive theliquid and a gas input channel to receive the pressurized gas. Thehousing also includes the mixing chamber to apply the pressurized gas tothe liquid and a slot or plurality of nozzles along the bottom length ofthe housing aimed at the polishing pad 106 to distribute the energizedfluid 314 across the polishing pad 106. In some embodiments, the housingor individual nozzles can be configured to rock back and forth asenergized fluid 314 is being dispensed to further enhance the looseningaction of the energized fluid 314 by continually altering the angle ofimpact of the energized fluid 314 on the pad 106.

As indicated by the ‘H’ dimension labeled in FIG. 3B, the pressurizedgas energized fluid delivery unit 312 can be disposed from approximately10 mm to approximately 100 mm above the polishing pad 106 duringapplication of the pressurized gas energized fluid 314. The vacuumsuction unit can be disposed from approximately 4 mm to approximately 10mm above the polishing pad 106 during application of the pressurized gasenergized fluid 314.

In some embodiments, the fluid that is energized can be deionized water(DIW) and/or cleaning chemistry. The temperature of the fluid can befrom 20 C. to 90 C. Other temperatures can be used. In some embodiments,the air pressure applied to energize the fluid can be in the range fromapproximately 40 PSI to approximately 140 PSI. Other pressures can beused. The liquid flow rate can be in the range from approximately 100ml/min to approximately 2 L/min. Other flow rates can be used. Thedroplet speed can be in the range from approximately 100 m/s toapproximately 300 m/s. Other droplet speeds can be used. In someembodiments, the cleaning chemistry can be, for example, dilutedpotassium hydroxide (KOH) when using, for example, SemiSperse® SS12slurry manufactured by Cabot Microelectronics Corporation of Aurora,Ill.

In some embodiments, a scraper, beater, and/or a rotating bristle brushmay selectively, continuously, or intermittently contact the polishingpad 106 to further help loosen and dislodge residue and debris. The useof a scraper, beater, and/or a rotating bristle brush may be selectivelyapplied by the controller 118. An optical sensor can be used to inspectthe pad 106 and provide information to the controller 118 as to thestatus of the pad 106. Based on the status of the pad 106, thecontroller 118 can determine if the pad should continue to be treatedwith energized fluid, if higher energy should be applied to the fluid(e.g., heat, pressure, acoustic energy, etc.), or of the pad shouldreceive contact from a scraper, beater, and/or a rotating bristle brush.

As indicated above, the energized fluid can alternatively be thermallyenergized to change state. As with acoustically and pressurized gasenergized fluid, thermally energized liquid forced to change into gas(e.g., using an ultra-pure DIW to steam generator) can be used toeffectively dislodge residue and debris from large areas like polishingpad grooves and also from smaller areas like polishing pad pores. Asnoted, this capability provides for high cleaning efficiency of thepolishing pad as compared to conventional pad cleaning methods. Thethermally energized gas removes particles via heat transfer. Becausethis method has a lower fluid flow rate, not only is DIW conserved, theamount of splash is drastically reduced and therefore, there issubstantially less slurry residue build up within the system 100.

FIGS. 4A through 4C depict top, side, and front views respectively of anenergized fluid delivery assembly 112 (FIG. 1) that includes a thermallyenergized fluid delivery unit 412 that is adapted to delivery thermallyenergized fluid 414 to the polishing pad 106 while vacuum suction unit116 removes dislodged residue and debris. In some embodiments, thethermally energized fluid delivery unit 412 can include a heater tovaporize cleaning fluid. The vaporizing chamber within the thermallyenergized fluid delivery unit 412 can be rectangular with dimensions inthe range of approximately 5 mm×50 mm to approximately 15 mm×1500 mm.Other sized vaporizing chambers can be used. For example, with apolishing pad radius of 15 inches, a vaporizing chamber with a length of15 inches may be used. Likewise, the vacuum suction unit 116 can be thesame length.

In some embodiments, shorter length vaporizing chambers can be used inthe thermally energized fluid delivery unit 412 where the delivery unit412 is adapted to be swept from the center of the pad 106 to the edge ofthe pad 106. In such embodiments, the fluid delivery arm 114 (FIG. 1),can be used to sweep the thermally energized fluid delivery unit 412across the pad 106 radially. Alternatively, a separate gantry can beused to sweep the thermally energized fluid delivery unit 412 back andforth radially over the pad 106.

In some embodiments, the thermally energized fluid delivery unit 412 caninclude a housing with a liquid input channel to receive the liquid. Thehousing can hold a heating element that receives electrical energy tovaporize the liquid. The housing also includes the vaporizing chamber toapply the thermal energy to the liquid and a slot or plurality ofnozzles along the bottom length of the housing aimed at the polishingpad 106 to distribute the energized fluid 414 across the polishing pad106. In some embodiments, the housing or individual nozzles can beconfigured to rock back and forth as energized fluid 414 is beingdispensed to further enhance the loosening action of the energized fluid414 by continually altering the angle of contact of the energized fluid414 on the pad 106.

As indicated by the ‘H’ dimension labeled in FIGS. 4B and 4C, thethermally energized fluid delivery unit 412 can be disposed fromapproximately 4 mm to approximately 10 mm above the polishing pad 106during application of the thermally energized fluid 414. The vacuumsuction unit can be similarly disposed from approximately 4 mm toapproximately 10 mm above the polishing pad 106 during application ofthe pressurized gas energized fluid 414.

In some embodiments, the fluid that is energized can be deionized water(DIW) and/or cleaning chemistry. The temperature of the fluid can befrom 20 C. to 90 C. Other temperatures can be used. In some embodiments,the heat energy applied to energize the fluid can be in the range fromapproximately 2 Kcal (2 Cal) to approximately 2000 Kcal (2000 Cal).Other amounts of thermal energy can be used. The liquid flow rate can bein the range from approximately 100 ml/min to approximately 10 L/min.Other flow rates can be used. In some embodiments, the cleaningchemistry can be, for example, diluted potassium hydroxide (KOH) whenusing, for example, SemiSperse® SS12 slurry manufactured by CabotMicroelectronics Corporation of Aurora, Ill.

In some embodiments, a scraper, beater, and/or a rotating bristle brushmay selectively, continuously, or intermittently contact the polishingpad 106 to further help loosen and dislodge residue and debris. The useof a scraper, beater, and/or a rotating bristle brush may be selectivelyapplied by the controller 118. An optical sensor can be used to inspectthe pad 106 and provide information to the controller 118 as to thestatus of the pad 106. Based on the status of the pad 106, thecontroller 118 can determine if the pad should continue to be treatedwith energized fluid, if higher energy should be applied to the fluid(e.g., heat, pressure, acoustic energy, etc.), or of the pad shouldreceive contact from a scraper, beater, and/or a rotating bristle brush.

Turning now to FIG. 5, a flowchart depicting an example method 500 ofcleaning a CMP polishing pad is provided. Note that the steps listed canbe implemented using the system 100 either manually by an operator orautomatically by the controller 118 executing instructions or a program.In some embodiments, some steps may be performed manually while othersare performed automatically. Also note that while four steps are listedto illustrate the method 500, other sub-steps and compound orsupra-steps can be included to increase or decrease the number of steps.

After CMP processing has been performed on one or more substrates, anenergized fluid delivery assembly 112 is positioned above the CMPpolishing pad (502). In some embodiments, the energized fluid deliveryassembly 112 may be positioned over the pad 106 while CMP processing isperformed. In some embodiments, the method 500 may be performed whileCMP processing is being performed.

With the energized fluid delivery assembly 112 and the vacuum suctionunit 116 in place, the CMP polishing pad 106 is rotated and the fluid inthe energized fluid delivery assembly 112 is energized (504). In someembodiments, energizing the fluid can include applying acoustic energy,applying pressurized gas, applying thermal energy to change a liquid toa gas, or any combination of these methods.

The energized fluid is applied to the polishing pad 106 while the pad106 is monitored (506). The energized fluid can be applied directly tothe pad 106 and in some embodiments, the energized fluid can be sprayedat the pad 106 from continuously changing angles by pivoting theenergized fluid delivery assembly 112 or its output ports (e.g., slot ornozzles). The energized fluid delivery assembly 112 can also beoscillated in a radial direction relative to the pad 106 to cover thefull radius to the pad 106.

In some embodiments, the energized fluid can be simply be applied for afixed amount of time or a fixed amount of energized fluid can beapplied. In some embodiments, an optical sensor can be used to monitorthe pad 106. In some embodiments, the vacuum suction unit 116 caninclude one or more sensors to determine if anything more than energizedfluid is being removed from the pad 106 and thus, that the pad 106 isclean. Thus, cleaning completion can be determined based upon the pad106 receiving a predefined amount of energized fluid, based on apredefined amount of time passing, or based upon feedback from one ormore sensors providing status of the pad (508).

Accordingly, while the present invention has been disclosed inconnection with the preferred embodiments thereof, it should beunderstood that other embodiments may fall within the spirit and scopeof the invention, as defined by the following claims.

The invention claimed is:
 1. A chemical mechanical polishing (CMP)system comprising: a polishing pad configured to be rotated on a platen;a polishing head configured to hold a substrate against the polishingpad; and an energized fluid delivery assembly configured to apply anenergized fluid to the polishing pad to dislodge slurry residue anddebris from the polishing pad.
 2. The CMP system of claim 1 wherein theenergized fluid delivery assembly includes an acoustically energizedfluid delivery unit configured to impart acoustic energy to a fluid andto direct the energized fluid toward the polishing pad.
 3. The CMPsystem of claim 1 wherein the energized fluid delivery assembly includesa pressurized gas energized fluid delivery unit configured to impartenergy in the form of pressurized gas to a liquid and to direct theenergized fluid toward the polishing pad.
 4. The CMP system of claim 1wherein the energized fluid delivery assembly includes a thermallyenergized fluid delivery unit configured to impart thermal energy to aliquid sufficient to cause the liquid to change state to a gas and todirect the energized fluid toward the polishing pad.
 5. The CMP systemof claim 1 further including a vacuum suction unit configured to removeslurry residue and debris dislodged by application of the energizedfluid to the polishing pad.
 6. The CMP system of claim 1 furtherincluding a controller operative to monitor the polishing pad todetermine if the polishing pad has been cleaned.
 7. The CMP system ofclaim 1 wherein the polishing pad is configured to be cleaned when CMPprocessing is not being performed.
 8. An apparatus for cleaning achemical mechanical polishing (CMP) polishing pad, the apparatuscomprising: an energized fluid delivery assembly configured to energizea fluid and apply the energized fluid to a CMP polishing pad to dislodgeslurry residue and debris from the polishing pad; and a vacuum suctionunit configured to remove the dislodged slurry residue and debris. 9.The apparatus of claim 8 wherein the energized fluid delivery assemblyincludes an acoustically energized fluid delivery unit configured toimpart acoustic energy to a fluid and to direct the energized fluidtoward the polishing pad.
 10. The apparatus of claim 8 wherein theenergized fluid delivery assembly includes a pressurized gas energizedfluid delivery unit configured to impart energy in the form ofpressurized gas to a liquid and to direct the energized fluid toward thepolishing pad.
 11. The apparatus of claim 8 wherein the energized fluiddelivery assembly includes a thermally energized fluid delivery unitconfigured to impart thermal energy to a liquid sufficient to cause theliquid to change state to a gas and to direct the energized fluid towardthe polishing pad.
 12. The apparatus of claim 8 further including acontroller operative to monitor the polishing pad to determine if thepolishing pad has been cleaned.
 13. The apparatus of claim 8 wherein theapparatus is configured to clean the polishing pad when CMP processingis not being performed with the polishing pad.
 14. A method of cleaninga chemical mechanical polishing (CMP) pad, the method comprising:positioning an energized fluid delivery assembly over a CMP polishingpad; rotating the polishing pad on a platen; energizing a fluid withinthe energized fluid delivery assembly; applying the energized fluid tothe polishing pad to dislodge slurry residue and debris; and removingthe dislodged slurry residue and debris using a vacuum suction unit. 15.The method of claim 14 wherein energizing a fluid within the energizedfluid delivery assembly includes energizing the fluid within anacoustically energized fluid delivery unit configured to impart acousticenergy to the fluid.
 16. The method of claim 14 wherein energizing afluid within the energized fluid delivery assembly includes energizingthe fluid within a pressurized gas energized fluid delivery unitconfigured to impart energy in the form of pressurized gas to a liquid.17. The method of claim 14 wherein energizing a fluid within theenergized fluid delivery assembly includes energizing a fluid within athermally energized fluid delivery unit configured to impart thermalenergy to a liquid sufficient to cause the liquid to change state to agas.
 18. The method of claim 14 further including monitoring thepolishing pad to determine if the polishing pad has been cleaned. 19.The method of claim 14 wherein applying the energized fluid to thepolishing pad is performed when CMP processing is not being performed.20. A system comprising: a processor; and a memory storing instructionsexecutable by the processor, the instructions operative to: position anenergized fluid delivery assembly over a CMP polishing pad; rotate thepolishing pad on a platen; energize a fluid within the energized fluiddelivery assembly; apply the energized fluid to the polishing pad todislodge slurry residue and debris; and remove the dislodged slurryresidue and debris using a vacuum suction unit.